Elevator controls



April 29, 1958 R. A. BURGY 2,832,437

ELEVATOR CONTROLS Filed Jan. 2. 1957 I 5 Sheets-Sheet 1 5 2/ H f I I I IIIIIPIIIIIIIHAHE INVENTOR.

P24 YMO/VD A BURGY April 29, 1958 R. A. BURG! 2,832,437

ELEVATOR CONTROLS Filed Jan. 2,, 195'? 3 Sheets-Sheet 2 INVENTOR.

F64 YMO/VD A. 5096 Y FOR/V5 S April 29, 1958 R. A. BURGY ELEVATOR CONTROLS Filed Jan. 2. 1957 ,a TOR/V5793 3 Sheets$heet 3 INVENTOR.

United States Patent I Cg A 23,332,437 Patented Apr. 29, 1958 ELEVATGR CONTRQLS Raymond A. Burgy, Maumee, Ohio, assignor to Toledo Scale Corporation, a corporation of Ohio Application January 2, 1957, Serial No. 632,664

11 Claims. (Cl. i87--29) This invention relates to improved circuits for elevator control and signalling systems.

An object of the invention is to facilitate control and signal functions in elevator systems.

Another object is to simplify the circuits required for signalling and controlling elevators.

A further object is to reduce the amount of equipment involved in performing signal and control functions and to enable existing equipment to be modified by enlarging its operating functions inexpensively.

An additional object is to establish selected operating n'ograms for an elevator system upon the coincidence or" certain service requirements and certain time intervals. Specific objects subsidiary to this primary object are to establish a program upon the coincidence of a plurality of service demands of predetermined levels and a given interval in the timed operating cycle of the system, and to establish one of a plurality of alternative programs during a given interval by selecting that program in response to service demand.

In realizing the above objects this invention can be applied to cooperating self-maintaining circuit controllers or relays which are mutually exclusively operated. Such controllers are employed in the controls establishing the op erating pattern of a system, travel direction controls, and as floor selector controls all requiring the Operation of one controller to exclude other controllers. One such controller includes a relay arranged to exert sufiicient magnetic attraction to a contact actuating armature to maintain the armature displaced when deenergized after it has been energized to attract that armature from its relaxed position, and to release that armature from the displaced position only when the relay is energized to overcome the residual magnetic forces suihciently to release the armature and permit it to return to its relaxed position. Each such relay can be arranged to insure that the armature of associated relays are in their relaxed position when its :nmature is in its displaced position by interconnections which cause their energization in a manner to overcome any magnetic force which may be maintaining their armature displa ed at the same time the first relay is energized to effect such displacement. One particular combination functioning in this manner employs two or more relays each provided with a core which can be magnetized by a first winding to displace an armature and demagnetized sufllciently to release the armature by a second winding. Each winding is provided with an individual and an electrically common terminal and both are energized when the relay is to be operated, the first Winding overcoming the effect of the second winding when both are energized. Each second winding of the group of relays ha its individual terminal connected to tr e individual terminal of each first winding of the group through a rectifier. When current is passed through the first winding of a given relay, it also passes through the second winding of all relays of the group thereby insuring that all but the given relay have their armatures dropped out. The armature of the given relay is maintained disphccd by the residual f2 magnetism induced by the magnetic force of its first winding until current is passed through another relay of the group or through the second windings alone.

In accordance with the above, a principal feature of this invention is to insure the reset of a group of relays by intercoupling and energizing reset means of a plurality of the relays.

Another feature involves intcrconnectig the reset means of a group of latch type relays with the primary windings of those relays so that upon the passage of current through one primary winding a plurality of reset means are actuated.

An additional feature is the utilization of unidirectionally conductive elements in circuit with interconnected reset means for latch type relays to avoid sneak current paths.

The above and additional objects and features of this invention will be appreciated to a greater extent from the following detailed description when read with reference to the accompanying drawings wherein:

Fig. l is a partially sectioned elevation of a magnetic latch type relay of a type utilized in this invention;

Fig. ll is a schematic diagram of an elevator floor selector machine and a family of latch type relays supplementing the floor selector functions in accordance with this invention; and

Ill is a schematic diagram of a program controller for an elevator system which is subject to a clock controlled group of latch type relay circuits embodying features of this invention.

Fig. I shows a magnetic latch type relay wherein the core 1 is a composite structure including a readily magnetizable portion 2 of low magnetic retenti'vity such as soft iron and a second magnetizable portion or slug 3 of relatively high magnetic retentivity such as Alnico No. 5, an alloy of 8% aluminum, 14% nickel, 24% cobalt, 3% copper and the balance iron. Slug 3 is positioned between core portion 2 and a magnet frame 4 also of low retentivity material. secured to the core 1 by a. machine screw 5. The magnetic circuit is completed from frame 4 to armature 6 which is hinged on the frame by means of slots 7 which fit over split fingers 8 of the frame. As in the case of the other portions of the magnetic circuit other than slug 3, armature 6 is of low rentivity material, in practice a relay steel containing about 2.5% silicon to reduce any aging tendencies of the magnetic properties. The core and frame are secured to a mounting bracket 9 by means of machine screws which secure the bent portions of frame fingers 8 to corresponding bracket portions.

Two energizing coils formed in a single coil assembly 1t) are mounted on core I. These coils are conventionally Wound one upon the other, however, for purposes of clarity they have been shown discrete and in axial alignment in the drawing. The larger coil it represents the primary or pickup coil of the relay which when energized functions to pickup or pull in the armature 6 against the core 2 and to magnetize slug 3 sufficiently to maintain the magnetic forces in the circuit at a level to hold the armature against the core when the winding is deenergized. The smaller coil 12 represents a subsidiary or drop out coil which can be energized to oppose the magnetic forces of the pickup coil 11. The coil assembly ll) is mounted on the core 1 by positioning it around the core and securing it against axial displacement with a bendable tab 13 secured to the frame 4 by machine screw 14. Tab 13 is threaded through coil assembly 10 as it is slid over core 1 and is bent against its free end when the opposite end of the coil abuts against the head of screw 14.

Coils 11 and 12 can be energized by separate taps eX- tending to individual terminals or as discussed below they can be provided with a common terminal and a single individuul terminal. Taps and 16 are connected to the spaced apart ends of coils 11 and 12 respectively while tap 17 is common to their adjacent ends in the illustrated relay. When so arranged it is advantageous to wind coil 12 in the opposite direction from coil 11 to enable oppos ing magnetic forces to be developed in those coils when similarly energized.

A mounting panel 18 of insulating material such as glass-fiber-illed resin carries terminal screws 19 for the relay coils and contacts, and support bracket 9 secured thereto by screw 29. Taps 15, 16, and 17 are connected to terminal screws 1.9 by suitable connectors 21 on the face of the panel opposite the terminal portions of those screws. Similarly, the stationary contactor portions 22 of the relay armature actuated contacts 23 are secured to the panel by their terminal screws.

Armature 6, is shown in its relaxed state with compression spring 24 extended and contacts 23 separated from contactors 22. Spring tends to move armature 6 away from core 1 and it is primarily the force offered by this spring which must be overcome by the pickup coil when energized. This spring force also aids the resetting action of the drop out coil and reduces the force required by that coil. The degree of separation of the armature from core 2 when the relay is in its relaxed state is adjustable by virtue of back stop 25. When the armature is drawn to the core, the double break contacts 23 are properly seated on their contactors 22 by virtue of their rocking of the flexible mounting means connecting them through extension 26 to the atrmature. Flexibility is afforded by spring 27 maintained about column 28 by screw 29 so that it tends to urge contact bridge 30 toward the contactors 22 so they are engaged with uniform pressure over the contact faces.

The above structure is subject to many variables in establishing its desired operating characteristics including the number of ampere turns provided by each winding, the air gaps present in the magnetic circuit, particularly between the armature and core, the coercivity of slug 3, and the size of the slug. Since all of these are interrelated in a manner well known to those skilled in the art further details of the correlation of these factors is unnecessary. It is to be recognized that the pull-in force of coil 11 should exceed the drop out force of coil 12 sufficiently to draw the armature 6 against core 1 and to magnetize core 3 sufficiently to hold armature 6 when the coils are no longer energized. Further the force offered by coil 12 and thus its ampere turns should be sufficient to overcome enough of the residual magnetism to enable spring 2- to return the armature to it's released position against backstop and yet must be limited so that it will not reclose the armature by rem-agnetizing the core 1 with the opposite polarity. This relationship can be maintained by employing a slug 3 which is about one twenty-fifth of the length of the total magnetic circuit with a pickup coil lit generating four times the ampere turns of the drop out coil.

A number of relays 31 having characteristics of those disclosed above are shown in Fig. 11 in circuits arranged to cooperate with a portion of the control apparatus of a car commonly known as a floor selector machine 32. The floor selector establishes circuits for an elevator car in succession as the car proceeds along its hatchway whereby the car functions are actuated in accordance with the actual or effective car position. The floor selector represented is made up of a two coordinate array of stationary contacts 33 arranged in columns or lanes where they perform similar functions and in rows generally perpendicular to the lanes where they are associated with different functioning circuits for a single floor or landing. Thus, eight rows of contacts are shown on selector 32 to serve eight landings and six columns of contacts en able at least six circuits to be actuated at each floor. Each of the circuits connected to the floor selector is established by means'of a brush 34 arranged to be carried along the lane of contacts and engage one or more of the contacts in a lane at a time, depending upon its length along the lane and the contact separation. A crosshead or carriage 35 supports brushes 34 and can be moved parallel to the contact lanes by means of a drive coupled to the elevator lifting mechanism through shaft 36. When the elevator is in motion or is conditioned to move, the shaft 36 is rotated to drive sprockets 37 engaging the carriage supporting chains 33 extending over sprockets 39 on idler shaft 49. The position of the crosshead and its brushes thus are continually in a position with respect to the rows of landing contacts corresponding to the effective position of the elevator car.

The door selector represented in Fig. II is employed in many existing elevator controls. By virtue of the short brushes andcontacts, circuits are established through the selector only momentarily. It is often desirable to maintain a circuit signifying the position of a car in its hatchway until the car movement actuates the next succeeding circuit by causing a brush to be moved to its next contact on the floor selector. One application of such a circuit is that energizing the direction preference relays for a car to indicate the location of calls with respect to car position and thus the direction in which a car will be required to travel to serve those calls. The car position can be indicated in a circuit performing that function by providing a series family of normally closed contacts wherein individual contacts correspond to the landings and call indicators for the landings are connected effectively above and below respective contact to indicate up and down calls. By opening the contact pair corresponding to the landing at which the car is positioned or which the car has last passed until another contact pair is opened, the series chain is broken at the effective car position to deenergize a direction preference relay for the direction beyond the car unless a call is registered beyond the car. Such a call establishes an energizing circuit from the position in that chain of contacts corresponding to the landing for which or at which that call is registered through the chain to the source.

When existing equipment is altered to include direction preference circuits or the like, it has been necessary to either replace the floor selectors of the above type or in essence rebuild them. Such a practice is nneconomical and is to be avoided if possible. The circuit of Fig. 11 illustrates one means of avoiding this requirement and enabling the direction preference functions to be performed without modification of the floor selector. This is accomplished by actuating latching relays 31 corresponding to the several landings and numbered accordingly from L1 through L8 to signify the first through the eighth landings. Thus, as brush 49 engages a contact such as of the fifth landing of the lane of landing contacts, 41 through 48 corresponding in the units digit to the floor served, it energizes relay L5 for the fifth landing and insures the reset of all other landing relays. These relays in turn can be provided with back contacts connected in a series array (not shown) to correspond to the normally closed contact family of the above summarized circuit.

Energization of relay L5 initially can be considered as conventional since current from alternating current source 50 passes from line 51 through a unidirectionally conductive device 52, advantageously a selenium rectifier rated to withstand 220 volts in the back direction, along lead 53 to branch 54, through a pickup coil (not shown) to lead 55 to floor selector contact 45, brush 49, lead 56 in the traveling cable 57. When the car is in service, the circuit is completed through one or both of two relay contacts AM of the main switch relay (not shown) or CLA of the door closing control relay (not shown) which couples lead 56 to line 58 and thence to source 50. It will be noted that each relay 31 is provided with three terminals. In the case of relay L5 terminal 54 is connected to a common tap to a pickup and drop out coil as shown in Fig. I and S5 is the terminal individual to the pickup coil while terminal 59 is individual to the drop out coil. Current from 54 thus flows through both coils, the drop out current passing from 54 through the drop out coil to 59, through lead 6% and unidirectionally conductive element or rectifier 61 to junction 62 with lead 55. The drop out coil is wound in opposition to the pickup coil but as explained above the magnetic forces developed by it are overcome by the pickup forces when both coils are energized.

As brush 49 moves oh contact 45 of the floor selector relay L5 is deenergized. Its armature and the contacts actuated thereby are maintained in the position they as sumed when the energizing current was flowing, however,

- since the magnetic latch action of the relay is effective due to the residual magnetism within the magnetic structure.

Further progress of the crosshead 35 along the contact panel establishes another circuit in the lane including contacts 41 through 48. If the car were set to travel downward contact 44 of the fourth landing would be engaged by brush 49 or if upward travel were dictated contact 46 of the sixth landing would be engaged. Assuming upward travel, the engagement of contact 46 by brush 49 would energize relay L6, as outlined above,

causing its pull-in force to prevail over its drop out force to displace and magnetically latch its contacts.

An auxiliary or reset circuit would also be established when brush 49 engaged contact 46 to energize the drop out coil of relay L5 and incidentally all other relays 31 of the group with sufiicient current to overcome the latching force and permit the armature of the relay or relays to return to its or their relaxed or deenergized position. This circuit is in parallel with the latch of relay L6 across lead 53 and lead 63 to contact 46 and is established by virtue of jumper 64 interconnecting the individual terminal of each drop out coil. Thus, as relay L6 is energized relay L5 is reset by current flowing from lead 53 through branch 54, the drop out coil of L5 to terminal 59, thence to junction point 65, jumper 64, junction point 66 for relay L6, lead 67 connected to the individual terminal of the drop out coil of L6, rectifier 68 and lead 63 connected to source 5 0. The pull-in coils of all relays but that one having its floor selector contact engaged by brush 49 are maintained deenergized by the rectifiers in their drop out coil circuits poled to pass current in the same direction with respect to the controller or floor selector as rectifier 52 so that only the drop out force is gen erated. Thus, the current which might otherwise flow in the pull-in coil of relay L5 from 54 to 55, through 62 and 60 to junction 65 and jumper 64 is barred by rectifier 61 and only the drop out force is imposed on the magnetic system of relay L5. Similarly, a drop out force is gen erated in relays L7, L8 and L1 through L4 without energizing their pickup coils.

As the crosshead 35 proceeds in its motion along the contacts, relays are successively energized and upon each energization all other relays of the group are subjected to a drop out force. In this manner the effective position of the car is maintained for the control functions of the system by virtue of the latched or energized condition of a relay corresponding to that position and, as the position shifts, the relay in correspondence therewith is ener ized and that corresponding to the previous position deenergized.

Another form of magnetic latch relay circuit including an interlocked resetting feature is shown in Fig. III. As in Fig. II, a relay of the type shown in Fig. I can be employed to advantage. T his circuit is an improvement over that disclosed in Patent 2,652,903 for Automatic Elevator Control which issued September 22, 1953, to J. H. Borden and W. A. Nikazy. It eifects major changes in the operating program of the elevator system with which it functions in accordance with the time of day and service demand by energizing an appropriate relay 6 of a group from a clock controlled contact and resetting other relays of the group when the contacts controlled by the given relay have been actuated.

In order to facilitate an understanding of the invention and to avoid confusion with the piror art features which would be combined therewith in practice, only the primary program controllers and the means for actuating them either by a timer alone or in combination with service demand responsive elements are shown in Fig. III. A large number of contacts actuated by the operating coils shown have been eliminated and several contacts which can be actuated in a manner well known to those skilled in the art have been shown without their actuating means. Correlation has been maintained between the actuating coils and their contacts by employing like reference characters. A marginal key has been provided wherein the conductors and elements have been indexed in accordance with their horizontal position in the figure. The left-hand column of the key sets forth these line index numbers. The center column of the key lists the reference characters of the operating coils located in a given line positioned in horizontal alignment therewith. The line location of contacts actuated by a coil are listed in the right-hand column of the key also in horizontal alignment with the coil position. Back contacts, those closed when the coil is deenergized and opened when it is energized, are diflerentiated from front contacts, those closed by energizing the coil and normally open, by underlining the numeral indicating the line in which they are shown. As in Fig, ll, all elements in the circuit of Fig. iii are shown in their deenergized condition.

The primary conrtollers set up subsidiary circuits in the controls which alter the operating pattern of the car or cars in a multicar system to best fulfill the current trafilc demand. Four programs are represented although it is to be understood that the system could be expanded or contracted to best meet the needs of the installation. These programs are an off hours program arranged to economically service a reduced demand and introduced by energizing relay at line 19, a down peak program providing for a preponderance of travel downward as at noon and in the evening and set up by energizing relay H3 at line 18, an oil peak program for essentially balanced up and down trafiic and set up by energizing relay H2 at line 17, and an up peak program providing for a preponderance of upward travel and a heavy demand and introduced by energizing relay H1 at line 16.

The programs can be selected manually by means of selector switch 70 including rotatable contact arm 7i connected through line 72 to one terminal of alternating current source 73 and engageable with one of a plurality of semicircularly arrayed stationary contacts 7 3', 75, 76, 77 and 78. Contacts 75, 76, 77 and 78 are connected to program relays H1, H2, H3 and H4 respectively by means of respective leads 79, 80, 81 and 82 all extending to line ii? which is connected to a second terminal of source '73. Contact 74 is engaged by arm 7 as shown, when it is desired to effect program changes automatically by enabling a circuit to be completed to the program relays through the common line 84 and the individual branches 85, 86, 8'7 and therefrom each including a respective program selector relay contact PSlA, PSZA, PS3A and PSdA respectively actuating H2, H2, H3 and H4.

Program selector relays are energized by clock controlled contacts alone or by the coincidence of oper of those contacts and others actuated by the to of certain conditions in the elevator sys or timer actuating mechanism m i simplified schematic form. of the invention, co four hour cycle, a movaule cont arm 9% which is connected to line $3 by 9i and driven by the timing mechanism through one revolution every twenty-four hours, and series of contacts as, 94 and 95, only tour a toe. ty-

of which are shown, which are successively engaged by the contactor. Contacts 92, 93, 94 and 95 can be positioned along the path of contactor 9i to correspond to moments in the cycle when it is appropriate to effect some change in the operating pattern of the elevator system. Thus, it will be assumed that the system is employed in a building having a sharp peak in demand for travel upward between eight and nine in the morning as might be occasioned in an oifice building by the arrival of occupants at the beginning of the work day a balanced flow of traffic from nine until four in the afternoon, 16:00 in the 24 hour cycle, and thereafter a heavy exodus followed at 17:00 by a very reduced demand.

Three clock controlled program selection relays PS1, PS3 and PS4 are employed to eilect the necessary changes in the program selection circuits at the appropriate in stance and to maintain the selection over given intervals. As in the case of those relays 31 controlled by the floor selector 32 of Fig. H the clock controlled contacts are closed only momentarily, for example for one minute; accordingly, these relays are of the latch type to maintain the program selection between contact closures. One program, either of? peak or oil hours, is in effect when all clock controlled relays are deactivated, thus the latch reset circuits include a reset connection which can be energized without pulling in any clock controlled relay. Further, provision is made by means of an interlock contact which was not shown in the circuit of Fig. ii to enable the currently operated latch relay to be reset only when another relay armature has been actuated to establish other circuits, since in the absence of such an interlock, the off peak or off hours program might be initiated momentarily between the instant of drop out of one clock controlled program relay and the pickup of the next such relay.

Assume that the off hours program is in efiect at sometime prior to eight in the morning and that the first contact 92 is set to be engaged by contactor 9% at that time. As contactor 9 engages 92 relay PS1 is energized by half-wave rectified current through its pickup-coil from line '72 through lead 96, rectifier 97, branches 98 and 99 to contact 92, contactor 9t and lead 91 to line 83. As soon as the armature of relay PS1 has been displaced by the pull-in force, contacts PS1 at lines 4 and are closed. The contact at line 4 completes the circuit for the reset coil of relay PS1 from branch 98 and the terminal common to the pull-in and drop out coils through branch ltlil connected to the individual terminal of the drop out coil, rectifier 1 3-1, poled to pass conventional current toward the timer as is rectifier 97, contact PS1, junction Hi2 and branch 99. The remaining reset circuits are also closed from lead 96 through the common terminals by means of branches 103 and 104 to the individual drop out coil terminals by means of branches 195 and 106 to junction points 197 and 108 respectively for relays PS3 and PS4. These junctions are connected by way of jumper 109 to junction 110 through rectifier 101 and branch ltltl and thence contact 92 to the source. Again the rectifiers 111 and 112 in the reset circuits of relays PS3 and PS4 bar the how of any current through the pull-in coils of these relays so that the drop out force overcomes their residual magnetism and causes the release of any displaced armature.

Contact PS1 at line it pulls in at the same instant the reset circuit is completed so that the opening of PS3 at line 12 or PS4 at line 14 does not release their associated circuits before the new circuit has been enabled. Relay PSIA in line 1%) can be actuated only while PS1 is closed. When energized, it closes a contact PS1A at line 16 to energize the up peak program relay H1. This closure requires another condition to be coincident with closed contact PS1, namely, the closure of contactCPA of a car call counting relay (not shown) which is energized when the number of car calls reach a predetermined level. When this demand arises, relay PSlA seals itself in at line 11 by bridging contact CPA so that the up peak program is maintained until contact PS1 is opened. Contact PSlA in line 15 is also held open during this interval to prevent the actuation of program selection relays PSZA and PS4A.

At nine in the morning contactor engages contact 93 to reset relay PS1 by energizing its drop out coil from lead 96 through branches 98 and to junction and jumper 109 thence from junction 113 through lead 114 to engaged contact 93 and source 73. The reset of all other latch relays is also assured by this circuit which carries current through their drop out coils also. With all clock controlled program selection relays deenergized, circuits are available to off peak and oil hours program relays PSZA and PS4A from line 72 through [end 115 and back contacts PSlA, PS3A and ECA to lead 536 and relay PS4A coil or through back contacts PSIA, i-SS-A and PS4 and front contact ECA of lead 117 to relay PSZA operating coil. Relay ECA (not shown) determines which of relays PSZA and PS4A are energized in this instance and relay ECA is energized by the service demands from the landings, e. g. the accumulated intervals of registration of landing calls. Thus, when the total delay in responding to landing calls falls below a given l vel, relay ECA is deenergized closing its contact at line 15 to energize relay PS4A and set up the off hours program while a rise in the delay in responding to landing calls to or above a given level which may be the same as or diiferent from the first level energizes relay ECA to open the back contact in line 15 and close contact ECA in line 11 whereby the off peak program is set up by the energization of relay PSZA. These two programs are available in the alternative through most of the day.

At four in the afternoon, 16:00, the down peak program is introduced by the engagement of contactor arm 9% with contact 94 thereby energizing relay PS3 through lead 118 to close the reset circuit at line 7 and partially complete the circuit for relay PS3A at line 12. Relay PS3A is energized to close contact PS3A at line 18 and to select the down peak program by energizing relay H3 when the number of landing calls in a first and a second group of landings each attain a certain level. These levels are monitored by means of a relay HPE (not shown) which is energized by a certain number of calls in a so-called express zone while a relay HPL not shown) is energized by a certain number of calls in a local zone. When both zones have the required number of calls registered, contacts HPE and HPL are closed at line 13 to energize PSSA which then seals itself in around contacts HPE and HPL by closing contact PS3A at line 12 and terminates the ofi peak or oil hours program then in effect by opening back contact PS3A in line 15.

The evening rush downward has terminated by five in the afternoon, hence, the oil hours program is placed in effect at that time by energizing clock controlled program relay PS4 and resetting relay PS3. Contactor arm 90 engages contact 95 at this time to complete a circuit to relay PS4 through branch 119. When relay PS4 pulls in it closes the reset circuits through contact PS4 at line 9, opens back contact PS4 at line 11 to insure the termination of the off peak program in the event the service demands failed to set up the down peak program, and closes contact PS4 at line 14 to energize relay PS4A closing a contact at line 19 to energize off hours program relay H4.

While the above disclosed latch and reset circuits have been shown utilizing a magnetic latch relay similar advantages and mode of operation could be attained with mechanical latch relays. Thus, a relay which effects the release of its latch mechanism from thereset to the latch position before the armature is released from its contact closing position can be employed, whereby the energization of both the pickup and drop out or reset means can be efiected simultaneously to close contacts, and, when the energization is removed, the latch engages before the armature is displaced from its energized, contact actuating position to maintain it in that position. One such relay has an armature travel beyoi l the contact actuating and latch position so that when the armature and latch are released simultaneously the latch is released to its effective position and bars travel of the armature out of its contact actuating range. When the reset circuit is energized alone, however, the armature is released enabling the relay to be reset under that condition.

It is appreciated that the invention will function equally well with the rectifiers poled in a manner opposite that shown. Thus, the rectifiers should all be poled in like manner with respect to the controller, the floor selector or timer, so that the relays are supplied with a half-wave rectified current of a given polarity and the rectifiers in the reset circuits bar the feeding back of that current from the pickup circuit into the common reset circuit.

In view of the above, it is to be understood that the embodiments described are intended only as illustrative of the invention. One skilled in the art might readily modify the invention or substitute alternative mechanisms, and utilize the circuits in other applications than set forth above without departing from its spirit and scope.

What is claimed is:

1. In combination in an elevator control, a plurality of relays each including an armature having a first position, a first coil displacing said armature to a second position when energized, a magnetic seal for maintaining said displaced armature in said second position, a second coil for overcoming the force of said magnetic seal to release said armature, means returning said released armature to said first position, a common terminal for said first and second coils, an individual terminal for each of said first and second coils, said relays being connected in a circuit including a source of electric energy, a connection from each common terminal to said source, a second connec tion between each individual terminal of said second coils, a unidirectional conductive device individual to each of said relays and connected between said second connection to said second coil terminals and the respective individual terminal of said first coil for each relay, and means to connect the individual terminal of said first coil of each relay to said source whereby the first coil of the corresponding relay is energized and the second coil of all relays of the plurality are energized.

2. In combination in an elevator control, a plurality of relays each including an armature having a first position, a first coil displacing said armature to a second position when energized, a magnetic seal for maintaining said displaced armature in said second position, a second coil for overcoming the force of said magnetic seal to release said armature, means returning said released armature to said first position, a common terminal for said first and second coils, an individual terminal for each of said first and second coils, said relays being connected in a circuit including a source of electric energy, a connection from each common terminal to said source, a second connection between each individual terminal of said second coils, a unidirectional conductive device individual to each of said relays and connected between said second connection to said second coil terminals and the respective individual terminal of said first coil for each relay, and means to connect said second connection to said source.

3. In combination in an elevator control, a plurality of relays each including an armature having a first position, a first means displacing said armature to a second position when energized, a latch for maintaining said armature in said second position, second means for releasing said latch when energized to release said armature, first terminals for said first and second means, second terminals for each or" said first and second means, said relays each being connected in a circuit including a source of electric energy, a connection from each first terminal to said source, a second connection between each second terminal of said second means, a unidirectionally COl'ldUCilX'G device individual to each of said relays and connected between said second connection and the second terminal of said first means of said respective relay, and means to connect the second terminal of said first means of each relay to said source whereby the second means of all relays are energized upon the energization of a first means of any one of said relays.

4. In combination in an elevator control, a plurality of relays each including an armature having a first position, a first means displacing said armature to a second position when energized, a latch for maintaining said armature in said second position, second means for releasing said latch when energized to release said armature, first terminals for said first and second means, second terminals for each of said first and second means, said relays each being connected in a circuit including a source of electric energy, a connection from each first terminal to said source, a second connection between each second terminal of said second means, a unidirectionally conductive device individual to each of said relays and connected between said second connection and the second terminal of said first means of said respective relay, and means to connect said second connection to said source.

5. in combination in an elevator control, a plurality of relays each including an armature having a first position, a first means displacing said armature to a second position when energized, a latch for maintaining said armature in said second position, second means for releasing said latch when energized to release said annature, first terminals for said first and second means, second terminals for each of said first and second means, said relays each being connected in a circuit including a source of electric energy, a connection from each first terminal to said source, a second connection between each second terminal of said second means, a unidirectionally conductive device individual to each of said relays and connected between said second connection and the second terminal of said first means of said respective relay, a normally open contact connected between said second connection and the second terminal of said first means of a given relay, said contact being closed when the armature of said given relay has been displaced to said second position, and means to connect the second terminal of said first means of each relay to said source.

6. in combination in an elevator control, a plurality of relays each including an armature having a first position, a first coil displacing said armature to a second position when energized, a magnetic seal for maintaining said displaced armature in said second position, a second coil for overcoming the force of said magnetic seal to release said armature, means returning said released armature to said first position, a common terminal for said first and second coils, an individual terminal for each of said first and second coils, said relays being connected in a circuit including a source of electric energy flowing in a single direction, a connection from each common terminal to said source, a second connection between each individual terminal of said second coils, a unidirectional conductive device individual to each of said relays and connected between said second connection to said second coil terminals and the respective individual terminal of said first coil for each relay, a family of contacts individually connected to said individual terminals of said first coils of respective relays, a movable brush engageable with a selected contact of said family, and a connection between said brush and said source.

7. in combination in an elevator control, a plurality of relays each including an armature having a first position, a first coil displacing said armature to a second position when energized, a magnetic seal for maintain" ing said displaced armature in said second position, a second coil for overcoming the force of said magnetic seal to release said armature, means returning said rc- 11 leased armature to said first position, a common terminal for said first and second coils, an individual terminal for each of said first and second coils, said relays being connected in a circuit including a source of electric energy flowing in a single direction, a connection from each common terminal to said source, a second connection between each individual terminal of said second coils, a unidirectional conductive device individual to each of said relays and connected between said second connection to said second coil terminals and the respec' tive individual terminal of said first coil for each relay, a family of contacts individually connected to said individual terminals of said first coils of respective relays and positioned in correspondence with the landings served by an elevator car subject to said control, a brush engage able with the contacts of said family, means moving brush to a selected contact corresponding to the effective position of said car, and a connection between said brush and said source.

8. ln combination in an elevator control, a plurality of relays each including an armature having a first position, a first coil displacing said armature to a second. position when energized, a magnetic seal for maintaining said displaced armature in said second position, a second coil for overcoming the force of said magnetic seal to release said armature, means returning said released armature to said first position, a common terminal for said first and second coils, an individual terminal for each of said first and second coils, said relays being connected in a circuit including a source of electric energy flowing in a single direction, a connection from each common terminal to said source, a second connection between each individual terminal of said second coils, a unidirectional conductive device individual to each of said relays and connected between said second connection to said second coil terminals and the respective individual terminal of said first coil for each relay, and a time responsive means for connecting individual terminal of a first coil of a selected relay to said source at a giveninstant.

9. In an elevator system, a plurality of relays each bar ing an activated and a deactivated condition, means to energize each relay to place it in its activated condition, means to maintain each relay in its activated condition, means to release each relay from its activated condition, a controller for said energizing means and said release means, a connection between said energizing and said 12 release means arranged to insure the deactivation of all other relays of said plurality upon the energization of am given relay of said plurality.

ill. in an elevator system, a plurality of relays each having an activated and deactivated condition, means to energize each relay to place it in its activated condition, means to maintain each relay in its activated condition upon the removal of said energizing means, means to release said maintaining means for each relay to place it in its deactivated condition, a timer controlling said energizin means and said release means, a connection bet een said energizing and said release means to insure the deactivation of all other relays of said plurality upon the energization of any given relay of said plurality,

plurality of elements responsive to demands for elevator service, a first operating program controller for said elevator system energized upon the concidence of the activation of the first of said relays and a respective one of said elements, and a second operating program controller for said elevator systemenergized upon the coincidence of the activation of the second one of said relays and the response of a plurality of said elements.

ll in an elevator system, a plurality of relays each having an activated and deactivated condition, means to energize each relay to place it in its activated condition, means to maintain each relay in its activated condition upon the removal of said energizing means, means to release said maintaining means for each relay to place -it in its deactivated condition, a timer controlling said energizing means and said release means, a connection between said energizing and said release means to insure t e deactivation of all other relays or" said plurality upon the euergization of any given relay of said plurality, a plurality of elements responsive to demands for elevator service, a plurality of operating program controllers for said elevator system, a circuit for energizing a plurality of said program controllers, said timer conditioning said relays to establish a portion of said circuit to said plurality of controllers, one of said elements being responsive to'a first given elevator service requirement to complete said circuit to one of said program controllers, and another one of said elements being responsive to a second gvcn elevator service requirement to complete said circuit to another of said program controllers.

No references cited. 

